The film, produced by Anurag Kashyap, is based on historical events during the Chittagong Uprising in the 1930s.
Spotted at the event were celebrities like Amitabh Bachchan, Shah Rukh Khan and Anil Kapoor.
The film, directed by Bedabrata Pain, stars Manoj Bajpai and Nawazuddin Siddiqui. Chittagong releases in cinemas on October 12.
In picture: A fan takes a photograph with Shah Rukh Khan